#1
Do the plate voltage differ beetween different sets of tubes?

So i should put new tubes in and measure the plate voltage or can i do that with the old tubes in?
Inspired by Ibanez RGA321F Prestige, Gibson Les Paul Standard
Powered by CAA OD100 standard+ , Mesa 2x12
Affected by Maxon OD808, Mad Professor Deep blue delay


#2
Plate voltage remains constant
The current draw is different for each set of tubes.

Long story short, you can't bias your new tubes using measurements from your old tubes.
#3
so i put the new tubes in, measure the plate voltage, shut off, put on the bias probe, turn it on again and measure the mA, and adjust bias until i get to what the weber bias calculator say for the specific plate voltage i got?
Inspired by Ibanez RGA321F Prestige, Gibson Les Paul Standard
Powered by CAA OD100 standard+ , Mesa 2x12
Affected by Maxon OD808, Mad Professor Deep blue delay